A Mass Spectrum Analysis of the Products of Ionization by Electron Impact in Nitrogen, Acetylene, Nitric Oxide, Cyanogen and Carbon Monoxide

Abstract

A mass spectrograph, designed for the identification of the products of ionization and dissociation by electron impacts in molecular gases is described.Ionization potential of nitrogen. A direct comparison in a nitrogen-argon mixture showed that the ionization potential of nitrogen is at least 0.04 volt less than that of argon. The ionization potential is therefore not greater than 15.65 volts, though it may be lower by as much as 0.1 volt.Analysis of ionization and dissociation products in ${\mathrm{C}}_{2}$${\mathrm{H}}_{2}$, NO, and ${\mathrm{C}}_{2}$${\mathrm{N}}_{2}$. The ions formed by electron impacts in these gases together with their appearance potentials in volts are as follows: Negative ${\mathrm{O}}^{\ensuremath{-}}$ ions appear in NO as reported by Tate and Smith. An ion of mass 27 found in ${\mathrm{C}}_{2}$${\mathrm{H}}_{2}$ is ascribed to ${\mathrm{C}}^{12}$${\mathrm{C}}^{13}$${\mathrm{H}}_{2}$. The abundance ratio ${\mathrm{C}}^{13}$: ${\mathrm{C}}^{12}$ was calculated to be 1: 100.